Professional journals of dentistry and medicine have documented the spread of infection that occurs in clinics, hospitals, patient rooms, public facilities and other noninstitutional settings when practitioners and staff fail to appropriately cleanse their hands. Given the often dire consequences of poor hygiene, practitioners must wash their hands with bewildering frequency. Alcohol, hydrogen peroxide, as well as iodine and chlorine containing compounds have long been recognized as effective antimicrobial and antiviral agents, thus their use in scrub and pre-surgical preparation is widely encouraged. However, recent studies have shown that repeated application of many of these compounds to the skin is physiologically damaging. In addition, when microbe populations are regularly subjected to specific antimicrobial chemical compounds, the microbes gradually evolve by developing chemical pumps which expel those compounds, thereby greatly reducing the effectiveness of the compound as an antimicrobial agent.
Certain metals have been shown to possess antiseptic qualities. Mercuric solutions, such as tincture of merthiolate and mercurachrome, were widely used in the twentieth century as antiseptics. However, studies showing that the use of such antiseptics resulted in the absorption of mercury through the skin, coupled with research indicating that the uptake of even small amounts of mercury resulted in the retardation of children, prompted their discontinuance. The search for alternative antiseptic compounds which do not damage the central nervous system, and which do not harm the skin and mucous membranes has been extensive.
Silver is a naturally-occurring metal that, when applied topically, has been shown to be lethal to a wide variety of disease-causing bacteria, fungi, molds, parasites, and viruses, yet relatively innocuous to the human body. Phoenician records from the period 700 to 100 B.C. indicate that silver vessels were used to keep vinegar, water and wine pure during long journeys and voyages. It is also known that early American settlers and pioneers used copper, gold and silver coins for medicinal and water purification purposes. The use of silver as a bactericide was documented as early as the late 1800s. In the past century, particularly the past two decades, silver has come to be widely recognized as an effective germicide and parasiticide. For such applications, silver has typically been used in the form of silver nitrate, silver oxide, or colloidal suspensions of silver compounds. For example, silver nitrate drops are routinely placed in the eyes of newborns in order to protect the eyes of infants—who might have become infected as they passed through the birth canal. Colloidal silver, either as elemental or silver oxide particulates, suspended in mineral oil or water bases, is being promoted for a wide variety of medicinal purposes via both internal ingestion and topical application. It is promoted as a treatment for mastitis and as a treatment for infections of the mucous membranes.
There is little indication that microbes have or can develop a resistance to silver, as it externally blocks respiration, rather than interfering with the internal metabolism of the organism.
In recent decades, extensive research has demonstrated that chelated silver is an active antimicrobial. The antimicrobial action reportedly occurs by blocking the respiration of microorganisms. Chelated silver is different from colloidal silver. Chelated means in solution, whereas colloidal means in suspension. In colloidal suspensions, minute silver particles are suspended or floating in an aqueous solution, and are not evenly dispersed throughout the liquid. Chelated solutions occur when a metal ion forms a heterocyclic ring with a bidentate ligand. Examples of bidentate ligands are carbonate and oxalate ions and ethylenediamine. As a general rule, five- or six-membered rings are favored. Because chelated silver ions are chemically bonded to nonmetallic ions, they are evenly dispersed throughout the solution. The even dispersal of chelated silver ions throughout the solution considerably enhances their antimicrobial action and effectiveness over time.
Three U.S. patents were issued to James W. Van Leuven covering a liquid antiseptic in which silver ions are chelated with sodium polypectate. U.S. Pat. No. 4,184,974 to Van Leuven discloses a liquid cleaner, lubricant and topical biocidal agent containing lauryl diethanolamide, propylene glycol, glycerine, sodium polypectate, a water soluble detergent, silver ions, and sufficient base to maintain pH within a range of 7.2 to 7.8, and distilled water. U.S. Pat. No. 4,267,168, which is a continuation of the application which issued as the '974 patent, discloses a method for treating external human tissue with the liquid cleaner, lubricant and topical biocidal agent disclosed in U.S. Pat. No. 4,184,974. U.S. Pat. No. 4,289,758, which is a continuation of the application which issued as the '168 patent, discloses a liquid biocidal agent containing about 100 to 400 parts per million sodium polypectate, about 13 to 250 parts per million silver ion, about 4 to 8% glycerine, sufficient base to maintain a pH in the range of from about 7.2 to 7.8, and distilled water.
A known drawback to the solutions patented by Van Leuven is that chelation of the silver ions lacks long-term stability. The instability is apparently due either to a gradual decomposition of the polypectate molecules or the gradual formation of extraneous compounds which have a greater affinity for the silver ions than to the polypectate molecules. The decomposition is accelerated in the presence of extreme cold or heat and light. The greater the heat or the greater the energy of the incident light, the more rapid the decomposition.